Correlation between binocular vision function and visual fatigue in school-age children with myopic anisometropia

We investigated the differences in binocular vision function and visual fatigue between school-aged children with myopic anisometropia and those with myopic isometropia. It also examined the correlation between myopic anisometropia and binocular vision parameters. One hundred school-aged (ages 6-13 years) children (43 boys and 57 girls) were divided into two groups: the myopic anisometropia group (interocular spherical equivalent difference ≥ 1.50 and < 4.00 D) and the myopic isometropia group as control group (interocular spherical equivalent difference < 1.00 D). Binocular vision parameters related to accommodation were analyzed, including accommodative amplitude, flexibility, relative accommodation, and convergence flexibility. Differences in visual fatigue scores between groups were also evaluated. Patients with myopic anisometropia show significant binocular visual dysfunction, including reduced accommodation amplitude, accommodative facility, and vergence facility, with a compensatory increase in positive relative accommodation. Although negative relative accommodation was similar between groups, anisometropic patients had more severe visual fatigue (higher ASQ-11 scores). In myopic patients without anisometropia, visual fatigue was mildly negatively correlated with accommodative facility. Clinically, binocular accommodation and vergence function should be carefully assessed in myopic patients, especially those with anisometropia, and visual fatigue interventions should include training of accommodative and vergence facility to enhance visual quality.